Manufacture of artificial icicles



United tates Patent 3 077,416 MANUFACTURE OF ARTIFICIAL ICICLES Joseph R. Ehrlich, 1793 Riverside Drive, New York, NY. No Drawing. Filed Sept. 22, 1961, Ser. No. 139,847 8 Claims. (Cl. 106-189) This invention relates to a viscous liquid composition especially useful in the formation of decorative imitation icicles and to a process for the preparation of these imitation icicles. The present application is a continuationin-part of application Serial Number 782,672, filed December 24, 1958, now Patent No. 3,001,885.

In keeping with the Christmas season, or at least the wintry associations of that season, it is customary to decorate Christmas trees with simulations of the natural phenomena which occur during that season. Such phenomena, of course, include snow and ice. The problems incident to a realistic reproduction of snow have already been solved so that it is possible to create a layer of snow indoors which captures much of the character of the actual. But to date the same cannot be said with respect to ice in the form of icicles. This is so because it is quite ditiicult to provide something with the properties common to all ice formations, that is, a basic solid material which is colorless, translucent, brilliant, perhaps here and there having an air bubble inclusion, and at the same time provide something which will yield ice formations of variegated size and shape. Both these characteristics should be present in order that the illusion of realism be not destroyed.

Hereto-fo-re attempts to meet the problems thus presented have often involved the use of glass and plastic which have been the only material comparable in appearance to ice, but the use of glass or plastic fails to meet the second desideratum alluded to above. Obviously the glass or plastic must be preformed and, in order for its use to be economically feasible, it must be cast. This necessarily means that there are severe limitations as to the number of sizes and shapes which can be made available, since obviously these are re'adymade, factory manufactured articles. With such limitations the possibility of achieving the objective of realism disappears.

It is an object of this invention to provide a new material for use in producing icicles in the home which in all of the respects already indicated will be eminently suitable.

Another object of this invention is to provide a viscous solution of certaincellulose esters which are suited for the producing of said artificial icicles.

It is a further object of the present invention to provide a process for making artificial icicles on Christmas trees andthe like.

Other and more detailed objects will be apparent from the following description and claims.

The material of the present invention is a liquid of considerable viscosity which can be poured from a bottle or squeezed from a collapsible tube at room temperature. When so discharged from its container over a tree branch or other support, the viscous liquid flows downwards with the depending portion thinning to a point in which condition the icicle freezes. The product is a selfsupporting, free-hanging, non-sticky mass at room temperature. It will be observed that the artificial product, just as in the case of a natural icicle, is held to its support without the use of hooks or other hanging device, being held to its support because it has itself formed about the support.

The icicle solution of this invention flows freely at room temperature and normal atmospheric conditions to form a pointed cone of an average length of about 3 to 7 inches, preferably 4 inches, within 1 to 5 seconds when mary solvent for the..cellulose ester.

released from a closed container in a quantity of about /2 oz. The flowing liquid gels spontaneously in mid-air after it has changed to the pointed cone-shaped form of about 4 to 7 inches inlength; the solution neither drips nor flows slowly to form neither a thread-like shape nor a lump. The solution develops a skin on the surface quickly which is dry to the touch yet is permeable to the solvent vapors to permit a gradual drying and hardening of the icicles. The solution dries clear without a pattern, Without blushing, permanent haze, grain or turbidity. There is a minimum of volumetric shrinkage during the drying process. Since it is to be used as a decoration on Christmas trees, the icicles at anytime, when dry or while still containing solvent, do not sustain a flame when ignited. The solution does not spread an objectionable odor, is not corrosive, poisonous or hazardous to handle.

It has been found after considerable experimentation that the objects of the present invention could only be accomplished with a viscous cellulose ester solution meeting certain minimum characteristics. Generally speaking, the viscous solution of the present invention must comprise:

(a) At least a two-component solvent system having an essentially predominantly high evaporation rate.

(b) One of the solvents in the solvent system must have a diiferent rate of evaporation than the other.

(0) The cellulose ester component must contain at least one of the cellulose esters more particularly defined below.

(d) The solution in addition to other properties, must be sufiiciently viscous to promote gelling in the time allotted for the formation of the icicle, and, at the same timeyit must be sutficiently fluent to permit a free flow ing out, so that the icicle can grow to the desired length and endin a point.

The solvent blends used in accordance with the present invention are non-inflammable and must be composed of at least two solvents even if one solvent alone would be sufiicient to dissolve the cellulose ester. One or both solvents can be co-solvents or secondary solvents, though a blend is preferred containing at least one good pri Additional solvents in very small quantities can be co-solvents or even diluents.

One solvent of the solvent system must evaporate at a faster rate than any other and the whole solvent system must be of the fast evaporation type to cause the spontaneous gelation of the solution at roomtemperature and normal atmospheric conditions.

The explanation of the gelation phenomenon has been explained in greater detail in my copending application Serial No. 782,672.

ride, ethylene chloride, cyclohexane, etc. The preferred ratio of methylene chloride to; secondary solvent is 8:2, though ratios from 9.5:O.S to 7.2:2.8 can be used to give spontaneous gelation, though the ratios containing less.

methylene chloride are less desirable because of flammability.

It is desirable to use a cellulose ester which is highly soluble in the proper solvent blends as expressed by high concentration at the saturation point and at the same time results in a solution of relatively low viscosity-the viscosity being such that a quantity of about /2, oz. of solution flows freely within 1 to 5 seconds to form a pointed cone of an average length of 3 to 7 inches after which time the cone gels. Thus two factors are important for the choice of the right cellulose ester: solubility-and 3 viscosity. In addition to the cellulose esters covered in my copending application Serial No. 782,672, I have found that I can also use cellulose propionate. Instead of using straight cellulose propionate it is easier to use a mixed ester having a high propionyl content and a low content of another carboxylic acid, such as acetic acid.

I have made successful experiments with a cellulose propionate-acetate having a propionyl content from 41.4 to 45%, an acetyl content from 4.4 to 6.6% and a hydroxyl content from 1.1 to 1.7%.

In accordance with one aspect of this invention it is desirable to use a cellulose ester solution which contains at least a minimum concentration of about 20% by Weight and preferably in the range of 20 to 35% by weight. As noted above, the total solids content of the icicle solution may vary from 30 to 54% by weight of the total composition. The non-ester solids dissolved in the icicle solution may vary from about 10% to about 18% by weight of the total solution. The non-ester solids are added to help avoid shrinkage and impart flame resistance and other desirable properties such as clarity, transparency, reduced brittleness, etc. Chlorinated biphenyls such as the Arochlors and chlorinated paratfin are the most useful. Other useful additives are certain aryl sulfonamide formaldehyde resins, Santolite MHP (see Example 2 below), organic bromine, boron or phosphorous compounds.

The viscosity of the icicle solutions of the present invention as distinguished from the viscosity of the various cellulose esters used herein and expressed as described above, are diflicult to determine because of the fast gelling of the solution. However, it may be stated that the viscosity of the icicle solutions will vary within the limits of 85 to 170 seconds and preferably in the range of 85 to 130 seconds. This viscosity is expressed as the falling time for a in. steel ball through in. of solution contained in a 1 in. wide tube at 25 C. and 760 mm. of Hg.

Instead of using a cellulose propionate or a mixed cellulose propionate ester I can also use blends of said cellulose propionate with certain other cellulose esters, such as cellulose acetate or cellulose acetate butyrate of the types mentioned in my co-pending application No. 782,672.

The following examples are further illustrative of the present invention and it will be understood that the invention is not limited to it.

EXAMPLE 1 25% p.w. cellulose propionate acetate 24:5 seconds viscosity 13% p.w. Arochlor 1254 (chlorinated biphenyl) are dissolved in 62% p.w. solvent blend consisting of:

80% p.w. methylene chloride 20% p.w. isopropanol Remarks.This water clear, viscous liquid is free fiowing; when a quantity of about /2 to A of an ounce of this is squeezed at room temperature onto the end of a tree branch through the opening of a collapsible metal tube, said opening having a diameter of inch, or even better having a slit like opening of the same size, this liquid will flow downwards in a cone-like shape until it has reached a length of about 3 to 5 inches. Sudden gelation and hardening of the surface of said cone at room temperature will stop any further movement or change of shape. The icicle-like product will become thoroughly rigid within a short time. It is odorless and self-extinguishing when exposed to the open flame of a match.

EXAMPLE 2 2830% p.w. cellulose propionate acetate, 10:3 seconds 12% p.w. Arochlor 1254 (chlorinated biphenyl) 4% p.w. Santolite MHP (arylsulfonamide formaldehyde resin) 56-54% p.w. solvent blend as in Example 1 Remarks.The properties of the resulting liquid are similar as described in Example '1.

EXAMPLE 3 31% p.w. cellulose propionate acetate, 10:3 seconds 14% p.w. Arochlor 1254 4% p.w. chlorinated paraffin (40% chlorine) 51% p.w. solvent blend consisting of:

75% p.w. methylene chloride 25% p.w. ethanol Remarks.-The properties of the resulting liquid are similar as described in Example 1.

EXAMPLE 4 20% p.w. cellulose propionate acetate, 10:3 seconds 7% p.w. /2 second butyrate (cellulose acetate butytrate) 13% p.w. Arochlor 1254 59% p.w. solvent blend as in Example 1 1% p.w. cyclohexane or carbon tetrachloride Remarks-The properties of the resulting liquid are similar as described in Example 1.

EXAMPLE 5 EXAMPLE 6 26% p.w. cellulose propionate acetate, 10:3 seconds 13% p.w. Arochlor 1254 61% p.w. of a solvent blend consisting of:

93% p.w. methylene chloride 7% p.w. isopropanol Remarks.-The properties of the resulting liquid are similar as described in Example 1.

EXAMPLE 7 17% p.w. cellulose propionate acetate, 24:5 seconds 3% p.w. cellulose acetate 10% p.w. Arochlor 1254 70% p.w. solvent blend as in Example 6 RemarksThe properties of the resulting liquid are similar as described in Example 1.

EXAMPLE 8 19% p.w. cellulose propionate acetate, 10:3 seconds 8% p.w. /2 second butyrate 11% p.w. Archlor 1254 62% p.w. solvent blend as in Example 6 Remarks-The properties of the resulting liquid are similar as described in Example 1.

EXAMPLE 9 18% p.w. cellulose propionate acetate, 10:3 seconds 4% p.w. cellulose acetate 10% p.w. Arochlor 1254 68% p.w. of a solvent blend consisting of:

93% methylene chloride 7% methanol Remarks.The properties of the resulting liquid are similar as described in Example 1.

EXAMPLE 10 18% p.w. cellulose propionate acetate, 10:3 seconds 4% p.w. cellulose acetate 10% p.w. Arochlor 1254 68% p.w. solvent blend consisting of:

93% p.w. methylene chloride 7% p.w. ethanol Remarks.-The properties of the resulting liquid are similar as described in Example 1.

EXAMELE 11 27% p.w. cellulose propionate acetate, :3 seconds p.w. Arochlor 1254 53% p.w. solvent blend consisting of:

95% p.w. methylene chloride 5% p.w. isopropanol The cellulose propionate acetate as used in Example l-11 has a Propionyl content ((3 11 0) of substantially 43.2% p.w. Acetyl content (CH CO) of substantially 5.5% p.w. Hydroxyl content (OH) of substantially 1.4% p.w.

in commercial products of this composition one can find variations from 41.4% to 45% propionyl, from 4.4% to 6.6% acetyl, and from 1.1% to 1.7% hydroxyl.

The viscosity was determined by a falling inch stainless steel ball in a solution in 90/10 acetone/ ethanol, in accordance With ASTM Method D 871-56.

The cellulose acetate butyrate (M2 second butyrate) as used in Examples 4 and 8 has substantially 37% combined butyryl and substantially 13% combined acetyl, a substantially combined cellulose residue of 50%, the latter containing substantially 2% free hydroxyl.

The viscosity was determined by ASTM Method D-1343-54T in the solution described as Formula A, ASTM Method 13-87 1-54T. Viscosity in poises are converted to ASTM seconds equivalent to values obtained under Method D-87l-48.

While the invention has been described with particular reference to specific embodiments, it is to be understood that it is not limited thereto, but is to be construed broadly and restricted solely by the scope of the appended claims.

I claim:

1. A viscous solution which is liquid and free flowing at normal room temperature in a closed container and which increases in viscosity rapidly and spontaneously to a point of gelation when released from said container and exposed to air at room temperature and normal atmospheric pressure consisting of a high evaportion rate solvent system consisting of methylene chloride and a secondary solvent selected from the group consistingof methanol, ethanol, n-propanol, isopropanol, cyclohexane, carbontetrachloride, ethylene dichloride'and mixtures thereof, and a cellulose ester component dissolved therein, the ratio of methylene chloride to secondary solvent being in the range of from about 9.5 :0.5 to 7222.8, said methylene chloride and secondary solvent having a substantial difference in vapor pressure, said solvent system having a vapor pressure in the range of about 30 mm. to 360 mm. of Hg at 20 C., said cellulose ester component containing as a principal and essential constituent a cellulose propionate acetate having from 41.4 to propionyl, and 4.4 to 6.6 aeetyl, said solution having a total solids content of from about 30% to 54%.

2. A viscous solution according to claim 1 wherein said solution has a viscosity of from to 170 seconds.

3. A viscous solution according to claim 1 wherein the total cellulose ester component comprises at least 20% by weight of the solution.

4. A viscous solution according to claim 3 wherein the total cellulose ester component comprises from about 20% to 35% by weight of the total composition.

5. A viscous solution according to claim 1 wherein cellulose propionate acetate constitutes from 50% to of said ester component.

6. A viscous solution according to claim 1 including a modifier selected from the class consisting of chlorinated biphenyl, chlorinated parafiins and arylsulfonamide formaldehyde resin.

7. A viscous solution according to claim 1 wherein said modifier is present in solution in the range of about 10% to 18% by weight of the total solution.

8. A process for making artificial icicles suspended directly from a support which comprises placing a small quantity of the composition of claim 1 on said support and allowing said composition to flow downwardly under the influence of gravity whereby an artificial icicle is formed.

References Cited in the file of this patent UNITED STATES PATENTS 2,003,655 Reid June 4, 1935 2,367,503 Hunter et al. Jan. 16, 1945 2,492,978 Fordyce et al. Jan. 3, 1950 2,669,521 Bierly Feb. 16, 1954 2,680,691 Olson et a1. June 8, 1954 2,739,070 Fordyce et al. Mar. 20, 1956 

1. A VISCOUS SOLUTION WHICH IS LIQUID AND FREE FLOWING AT NORMAL ROOM TEMPERATURE IN A CLOSED CONTAINER AND WHICH INCREASES IN VISCOSITY RAPIDLY AND SPONTANEOUSLY TO A POINT OF A GELATION WHEN RELEASED FROM SAID CONTAINER AND EXPOSED TO AIR AT ROOM TEMPERATURE AND NORMAL ATMOSPHERIC PRESSURE CONSISTING OF A HIGH EVAPORTION RATE SOLVENT SYSTEM CONSISTING OF METHYLENE CHLORIDE AND A SECONDARY SOLVENT SELECTED FROM THE GROUP CONSISTING OF METHANOL, ETHANOL, N-PROPANOL, ISOPROPANOL, CYCLOHEXANE, CARBONTETRACHLORIDE, ETHYLENE DICHLORIDE AND MIXTURES THEREOF, AND A CELLULOSE ESTER COMPONENT DISSOLVED THEREIN, THE RATIO OF METHYLENE CHLORIDE TO SECONDARY SOLVENT BEING IN THE RANGE OF FROM ABOUT 9.5:0.5 TO 7.2:2.8, SAID METHYLENE CHLORIDE AND SECONDARY SOLVENT HAVING A SUBSTANTIAL DIFFERENCE IN VAPOR PRESSURE, SAID SOLVENT SYSTEM HAVING A VAPOR PRESSURE IN THE RANGE OF ABOUT 30 MM. TO 360 MM. OF HG AT 20*C., SAID CELLULOSE ESTER COMPONENT CONTAINING AS A PRINCIPAL AND ESSENTIAL CONSTITUENT A CELLULOSE PROPIONATE ACETATE HAVING FROM 41.4 TO 45% PROPIONYL, AND 4.4 TO 6.6 ACETYL, SAID SOLUTION HAVING A TOTAL SOLIDS CONTENT OF FROM ABOUT 30% TO 54%. 